Author: Tammy Plotner

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The small constellation southern circumpolar constellation of Norma was originally charted by Abbe Nicolas Louis de Lacaille who named it. It was later adopted by the IAU as one of the modern 88 constellations. Octans contains the south celestial pole and spans 297 square degrees of sky – ranking 50th in size. It has 3 primary stars in its asterism and 27 Bayer Flamsteed designated stars within its confines. Octans is bordered by the constellations of Tucana, Indus, Pavo, Apus, Chamaeleon, Mensa and Hydrus. It is visible to observers located at latitudes between +0° and ?90° and its primary stars are best seen at culmination during the month of October.

Since Octans is considered a “new” constellation, there is no mythology associated with it – only Abbe Nicolas Louis de Lacaille’s love of all things science and what Octans is meant to represent. In Lacaille’s time, the octant was used to aid in celestial navigation and it was relatively a new addition, having just come upon the scene when invented by John Hadley in 1730. It was a tool which Lacaille used, but Octans also has other scientific means, which Lacaille was well aware. In Latin, the octan is the eighth part of a circle, so its dual-edged meaning is not lost on some of us! Just as the octant was used to measure Polaris position in the circumpolar north – now the octant became “Octans” – a permanent reminder of the tool forever engraved in the circumpolar stars of the south.

Let’s begin our binocular tour of Octans with Beta – the “B” symbol on our map. At one time, Beta Octantis was another star in located in the constellation of Hydrus. It was part of the tail and was the southernmost star catalogued by Dutch navigator Frederic de Houtman. Located about 140 light years from Earth, this yellow- orange class K (K0) giant star isn’t anything special – except for it helps to point the way to Nu. Located only 69 light years away from our solar system, Nu Octantis is a wonderful star because here we have an example of what our own Sun may one day become. Right now, it has given up on hydrogen fusion, waiting quietly and just beginning to expand into a giant star. Although it will take 100 million years, it will become more than 60 times brighter and 15 times larger than it is now. Although we can’t see it, Nu also has a companion star – one that orbits almost as close as Earth is to the Sun!

Now, have a look at Delta – the figure “8” shape – in your binoculars. Guess what? If you were standing on Saturn, Delta would be the pole star! But, since we’re not, we’ll take a look at Sigma – the “o” symbol. This faint beauty is about as close to the southern pole star as we can get. Sigma Octantis is a yellow subgiant star which just left the main sequence and is about to expand into a red giant star. It’s about twice as large as our Sun and about 270 light years away.

For a nice binocular site, take a look at visual triple star – the Gammas. It’s the “Y” symbol on our map. Or try a visual double star when you get a double slice of Pi, located just above Delta. That only leaves poor R Octantis – a variable star.

For a real big telescope challenge, try the closest NGC object to the southern pole – NGC 2573 (RA 04:41:42 Dec -89:20:04). Polarissima Australis is a faint galaxy – close to magnitude 14! Believe it or not, it was discovered by was discovered by Sir John Herschel at the Cape of Good Hope with an 18″ f/13 speculum telescope and has been the recent target of investigations looking for gamma ray bursters.

Sources:
Wikipedia
University of Illinois
University of Wisconsin

Star Chart courtesy of Your Sky.

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The small constellation of Norma is located south of the ecliptic plane. It was originally charted by Abbe Nicolas Louis de Lacaille who named it “Norma et Regula”. It was later adopted by the International Astronomical Union as one of the 88 modern constellations and its name shortened to Norma. It covers approximately 165 square degrees of sky and ranks 77th in size. Norma has 2 main stars in its asterism and 13 Bayer Flamsteed designated stars within its confines. It is bordered by the constellations of Scorpius, Lupus, Circinus, Triangulum Australe and Ara. Norma is visible to all observers positioned at latitudes between +30° and ?90° and is best seen at culmination during the month of July.

The constellation of Norma has one annual meteor shower associated with it – the Gamma Normids. Activity begins on or about March 11 each year, lasting through March 21 with a peak date of March 16. This meteor shower only produces 5 to 9 meteors per hour at maximum and has only been studied within the last 50 years, so activity rates are sporadic and understudied.

Since Norma is considered a “new” constellation, there is no mythology associated with it – only Abbe Nicolas Louis de Lacaille’s love of all things science and what Norma is meant to represent. Originally named Norma et Regula, this dim collection of stars in Lacaille’s native language would have been “L’Équerre et La Règle”, meaning “The Set Square and The Ruler”. While it is difficult to visualize a set of drafting tools from this set of stars, Norma’s brighter stars do produce a few nice angles that will help guide you to some of its many deep sky riches.

Let’s start off our binocular tour of Norma with the “Y2” symbol on our map – Gamma 1 and Gamma 2 Normae. In a constellation which has no alpha or beta designations, fourth magnitude Gamma 2 is the brightest star here. The yellow giant star is located about 125 light years from Earth, but in binoculars you’ll notice another companion – Gamma 1. This is an optical double star because Gamma 1 is 1500 light years away!

For a true binary star, hop north to Epsilon Normae – the backwards “3” symbol on our map. Comprised of a 4.5 magnitude primary star and a 7.5 magnitude secondary, Epsilon is spaced widely enough apart to be split with steady binoculars and easily with a small telescope. Oddly enough, when it comes to this fixed position binary star, both components are also spectroscopic binary stars, too… Making this a quadruple star system!

Now, hop south for Iota 1 Normae – but bring a telescope. This 4.6 magnitude A7 subgiant star is located 271 light years from our solar system and its 11th magnitude companion has a close separation of 11″. This pair orbit each other very quickly, making a full revolution in just about 26 years.

Ready for a little variability? Then let’s start with Mu Normae – the “u” symbol. Mu is suspected of being an Alpha Cygni variable, with a magnitude range of 4.87 at brightest to a minimum of 4.98. This A type supergiant star doesn’t quite pulse like Cepheid – it exhibits non-radial pulsations during its brightness changes which may last from several days to several weeks! To follow a variable star whose changes are hugely apparent, take a look at R Normae. Here we have a Mira-type variable. It might take 507 for its changes to occur, but when they do, R will go from being an easy to spot in binoculars magnitude 6.5 to a need a telescope and star chart to find it magnitude 13.9!

Now, identify Kappa Normae – because it’s a guidestar to two awesome open clusters. In average 10X50 binoculars, if you place Kappa to the top of the field of view, you’ll easily see NGC 6067 (RA 16:13.2 Dec -54:13) to the north. Possessing about 100 stars spread in 13 arc minute field, this magnitude 5.6 cluster resolves beautifully in a telescope. It contains its share of Cepheid variables, too, but look for a wonderful bar-like structure with a concentration at one end. It’s bright, rich and very photogenic! Would you like to look at one more variable star?

With Kappa still at the top of your field of view, you’ll spy another open cluster to the south. Now, here’s a bonus, because you’ll find variable star S Normae locate right smack dab in the middle of open star cluster NGC 6087 (RA 16:18.9 Dec -57:54). At a combined magnitude of about 5.5, this galactic star cluster is meant for binoculars and telescopes of every size. At its heart beats S Normae, a well-known Cepheid that range in brightness from magnitude 6.1 to magnitude 6.8 magnitude every 9.75 days like clockwork. This particular cluster has been used as a cepheid calibrator to judge reddening influences down the main sequences in these type of clusters. Besides, it’s pretty!

A great mid-sized telescope object is open cluster NGC 6134 (RA 16:27:46 Dec -49:09:06). At around magnitude 7, this rich open cluster spans a generous 7 arc minutes and displays its stellar finery. Home to Delta-Scuti variables and rich in metal content, you’ll like this one, because it will give you an opportunity to look for a rare variable blue straggler star discovered there in 2001!

Larger telescopes are needed to spot NGC 6031 (RA 16:07:35.0 Dec -54:00:54.0) to the northwest of Kappa, though. Now approaching magnitude 9, this open cluster is far more sparsely arrange and definitely less populated. At around 2 arc minutes in size, this relatively young galactic cluster is nearly solar in its metal content and a nice challenge for your lists.

How about a challenging globular cluster? Then try your hand at NGC 5946 (RA 15:35:28.5 Dec -50:39:34). Located more than 34,000 light years from our Sun, this 10th magnitude globular was discovered on July 7, 1834 by John Herschel. At class IX, it’s a loose structure, but a great challenge. Why does it look like it has fallen apart? Maybe because it has. This particular one has undergone core collapse!

Last on our list for Norma is Collinder 299 (RA 16 18 42 Dec -55 07 00). This sparse open cluster will be hard to distinguish from the background stars, but use the lowest magnification you have available. We’re looking at a very old open cluster and one that has its stars chemically tagged along with other disk stars to help “unravel the dissipative history of the Galactic disk”.

There are many other great objects in Norma to have a look at, too… So grab a detailed star chart and get “normalized”….

Sources: SEDS, Wikipedia
Chart Courtesy of Your Sky.

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The constellation of Musca was originally created by Petrus Plancius from the stellar observations of Dutch sea navigators Pieter Dirkszoon Keyser and Frederick de Houtman when exploring the southern hemisphere. Musca’s star patterns became known when it appeared on a celestial globe in 1597 and was considered a constellation named Apis when it was added to Johann Bayer’s Uranometria catalog in 1603, but it was misinterpreted as a fly instead of a bee! In 1752 Nicolas Louis de Lacaille renamed it to Musca Australis, the Southern Fly to avoid confusion with Apus. Today the name is simply Musca and it has survived the years – and the confusion – to become one of the 88 modern constellations recognized by the International Astronomical Union. Located south of the ecliptic plane and covering only 138 square degrees of sky, Musca ranks 77th in size among its peers. It has 6 main stars in its asterism and 13 Bayer Flamsteed designated stars within its confines. Musca is bordered by the constellations of Apus, Carina, Centaurus, Chamaeleon, Circinus and Crux. It is visible to observers located at latitudes between +10° and ?90° and is best seen at culmination during the month of May.

Since Musca is a “new” constellation, there is no mythology associated with it – only a bit of folklore. When Petrus Plancius drew the insect on his celestial globe in 1598, for some reason he didn’t put a name on the critter, although Frederick de Houtman had referred to it in his native Dutch as “the fly”. In 1603, Johannes Bayer also added it to his star charts as well – but misinterpreted the insect as a bee, calling it Apis. Apparently it was also charted in another 1603 work by Willem Janszoon Blaeu, who being Dutch, understood the correct language and labeled it as a fly. By the time it reached the hands of Abbe Nicolas Louis de Lacaille in 1752 it was corrected yet again to Musca Australis – the southern counterpart of Musca Borealis. No wonder the IAU was invented! It was finally shortened to just Musca and adopted as an official constellation in 1930.

Let’s begin our binocular tour of Musca with a look at its brighter star – Alpha Muscae – the “a” symbol on our map. This class B giant star is located about 305 light years from Earth and shines over 4500 times brighter than our own Sun. Is it hot? You bet. Alpha Muscae runs a stellar temperature of around 21,900 degrees Kelvin – so hot that most of its light is emitted in the ultra-violet range. It whirls around at its equator at a speed of 114 kilometers per second, making a full rotation in about 48 hours. And… it has a Beta Cepheid variable star heartbeat. It pulses. About every 2.2 hours it changes its magnitude just ever so slightly!

Now, hop over to Beta Muscae – the “B” symbol on our map. Beta is a binary star of almost equal magnitude. This pretty blue star isn’t easy to split and will require high magnification in a telescope and a fine, steady night of seeing. For an easier double star, try Eta Muscae (13h 15.4 min RA -67 55 Dec). You’ll find it wide, bright and easy… With a bonus binary star in the field, too! Theta Muscae (13h 08.1 min RA -65 18 Dec) is also another fine binary star that shows an interesting color contrast.

For both binoculars and telescopes, try your hand at globular cluster NGC 4833 (12h 59.6 min RA -70 53 Dec). At not quite magnitude 7, Caldwell 105 is well compressed and shows some great resolution in larger instruments. It was first discovered by Abbe Lacaille during his 1751-1752 journey to South Africa, and catalogued in 1755 – then later observed and catalogued by James Dunlop and Sir John Herschel whose instruments could resolve it into individual stars. Located about 21,200 light years from our solar system, it would be a whole lot brighter if it weren’t for the Milky Way Galaxy’s dust!

Keep your binoculars and telescopes handy for NGC 4372 (12h 25.8 min RA -72° 40 Dec). This slightly brighter globular cluster is a very loosely constructed Class XII discovered by James Dunlop on April 30, 1826. It’s very metal poor and observations by the XMM-Newton Telescope have shown the presence of close binaries which are “thought to play an important role in the stability of the clusters by liberating energy and delaying the inevitable core collapse of globular clusters”.

Small telescopes will enjoy open star cluster NGC 4815 (RA 12h 57m 59.0s Dec -64° 57′ 36.0″). What it lacks in size, it makes up for in richness. Unlike the “Jewel Box”, this little cluster suffers greatly from interstellar absorption. Enjoy this relative of the Hyades!

Mid-to-large telescopes will enjoy planetary nebula NGC 5189 (13h 33.6 min RA -65° 59 Dec). Nicknamed the “Spiral Planetary Nebula”, this little gem was discovered by John Herschel in 1835. Located about 3,000 light years away from Earth, NGC 5189 has been studied for its kinematic structure and contains an unusual expanding ring of gas that we see nearly edge-on.

While in Musca, take a look for the southern extension of the Coal Sack – a dark nebula. Located about 600 light years away, this obscuration cloud was was known to the people of the Southern Hemisphere in prehistoric times and has even been referred to historically as the “Black Magellanic Cloud”.

Sources: SEDS, Wikipedia
Chart Courtesy of Your Sky.

The constellation of Monoceros was originally charted on a work done by Petrus Plancius in the early 1600s for its biblical references, but its first historical reference appears in Jakob Bartsch’s star charts created of 1624 where it was listed as Unicornu. There is also a possibility, according to Heinrich Wilhelm Olbers and Ludwig Ideler’s work with older astrological charts, that Monoceros could have been referred to as “the Second Horse” – while historian Joseph Justus Scaliger also makes reference to it in his (mid 1500s) work with Persian astrological records. Regards of its origins, Monoceros was adopted as one of the 88 modern constellations by the International Astronomical Union in 1930 and remains on the charts today. It is a relatively dim constellation that consists of 4 main stars in its primary asterism and contains 32 Bayer Flamsteed designated stars within its confines. Monoceros spans approximately 482 square degrees of sky and is bordered by the constellations of Canis Minor, Gemini, Hydra, Lepus, Orion and Puppis. It is visible to all observers located at latitudes between +75° and ?85° and is best seen at culmination during the month of February.

There is one annual meteor shower associated with Monoceros which peaks on or about December 10 of each year – the Monocerids: The radiant for this meteor shower occurs near the border of Gemini and averages about 12 meteors per hour at maximum fall rate. It is best viewed when there is little to no Moon to interfere with the faint streaks and activity is at its most when the constellation reaches the zenith.

Because Monoceros is a relatively “new” constellation, there isn’t any mythology associated with it – but the Unicorn itself has a long history of mystery. You’ll not find this creature mention anywhere in mythology, but everywhere else! The unicorn is mention in the Bible, in accounts of natural history, in Chinese lore, Ethiopian artwork, medieval stories and religious art. It is depicted as a one-horned horse, thought to have existed somewhere at the edge of the known Earth.. and it still exists roaming the edges of the celestial sphere just between the northern and southern ecliptic plane. Fable or folklore? No matter which, it’s filled with many great and starry delights!

Let’s begin our binocular tour of Monoceros with its primary star – Alpha Monocerotis – the “a” symbol on our map. Hanging out in space some 144 light years from Earth, it’s not the brightest star in the constellation, nor is it particular special. Alpha is just another orange/yellow helium-fusing giant star, not a whole lot different than ours. Averaging about 11 times larger than our Sun and putting out about 60 times more light, Alpha’s hydrogen fuel tank went to empty about 250 million years ago. Now it just waits quiety, waiting for its helium shell to fade away… ready to spend the rest of its life as just another dense white dwarf star.

Now, take a look at Beta Monocerotis – the “B” symbol on our map. If you think it’s slightly brighter – you’re right. That’s because Beta has some help from two other stars, too! Put your telescope Beta’s way and discover what Sir William Herschel called “one of the most beautiful sights in the heavens”. This fantastic triple star star system is located about 690 light years from our solar system. As you watch it slowly drift by the eyepiece, you’ll know the names of the stars by which leave sight first… from west to east they are A, B and C. In this circumstance, it is believed the B and C stars orbit each other and the A star orbits this pair. All three are about 34 million years old and all three are dwarf stars. Close to each other in magnitude, this trio of hot, blue/white B3 stars each run a temperature of about 18,500 Kelvin and shine anywhere from 3200 down t0 1300 times brighter than our own Sun and spinning on their axis up to 150 times faster. A real triple treat!

For binoculars, have a look at visual double star Delta Monocerotis – the “8” symbol on our map. Located 115 light years from our solar system, this cool pair is worth stopping by – just to see if you can resolve it with your eyes alone! Don’t forget to try Epsilon Monocerotis, too. The backwards “3” on our map. Larger, steady binoculars may separate it and it’s easy for a smaller telescope. This is a very pretty gold and yellow combination binary star, seperated by about two magnitudes. You’ll find it on a number of observing lists. While there, take a look just two degrees northwest of Epsilon for T Moncerotis. This is a great Cepheid variable star with a period of 27 days and a magnitude range of 6.4 to 8.0. Those are the kinds of changes you can easily notice!

Our first deep sky binocular and telescope target will be magnificent Messier 50 (RA 07:03.2 Dec -08:20). This splendid open star cluster averages around magnitude 6 and was logged on April 5, 1772 by Charles Messier in his catalog on deep sky objects. Located about about 3,200 light years from Earth, it spans about 20 light years of space and contains about 200 stars. Inside this 78 million year old cloud is at least one red giant star – located just a little bit south of central. Can you spot it? How about the smattering of yellows amid the blue/whites?

Now head for equally bright NGC 2301 (6:51.8 Dec +00:28). This easily resolvable chain of stars can be seen in binoculars, but requires a telescope to resolve its individual members. Smaller telescopes will notice at least 30 members, while larger aperture can detect many more from this 80 member galactic star cluster. Located about 2500 light years away, be sure to see if you notice color in the stars here, too. This intermediate age open cluster has been studied for short-term variable stars and chemically peculiar stars. You’ll find this one on many challenging observing lists, too!

Time to hop to NGC 2244 (RA 6:32.4 Dec +04:52). The “Rosette Nebula” is a fine target for either telescopes or larger binoculars at a combined magnitude of 5. But, remember, combined magnitude isn’t true brightness! You’ll find the nebula here is quite faint and requires a good, dark, Moon-less sky. NGC 2244 is a star cluster embroiled in a reflection nebula spanning 55 light-years and most commonly called “The Rosette.” Located about 2500 light-years away, the cluster heats the gas within the nebula to nearly 18,000 degrees Fahrenheit, causing it to emit light in a process similar to that of a fluorescent tube. A huge percentage of this light is hydrogen-alpha, which is scattered back from its dusty shell and becomes polarized. While you won’t see any red hues in visible light, a large pair of binoculars from a dark sky site can make out a vague nebulosity associated with this open cluster. Even if you can’t, it is still a wonderful cluster of stars crowned by the yellow jewel of 12 Monocerotis. With good seeing, small telescopes can easily spot the broken, patchy wreath of nebulosity around a well-resolved symmetrical concentration of stars. Larger scopes, and those with filters, will make out separate areas of the nebula which also bear their own distinctive NGC labels. No matter how you view it, the entire region is one of the best for winter skies.

Now for NGC 2264 (RA 6:41.1 Dec +09:53). Larger binoculars and small telescopes will easily pick out a distinct wedge of stars. This is most commonly known as the “Christmas Tree Cluster,” its name given by Lowell Observatory astronomer Carl Lampland. With its peak pointing due south, this triangular group is believed to be around 2600 light-years away and spans about 20 light-years. Look closely at its brightest star – S Monocerotis is not only a variable, but also has an 8th magnitude companion. The group itself is believed to be almost 2 million years old. The nebulosity is beyond the reach of a small telescope, but the brightest portion illuminated by one of its stars is the home of the Cone Nebula. Larger telescopes can see a visible V-like thread of nebulosity in this area which completes the outer edge of the dark cone. To the north is a photographic only region known as the Foxfur Nebula, part of a vast complex of nebulae that extends from Gemini to Orion.

Northwest of the complex are several regions of bright nebulae, such as NGC 2247, NGC 2245, IC 446 and IC 2169. Of these regions, the one most suited to the average scope is NGC 2245 (RA 6:32.7 Dec +10:10), which is fairly large, but faint, and accompanies an 11th magnitude star. NGC 2247 is a circular patch of nebulosity around an 8th magnitude star, and it will appear much like a slight fog. IC 446 is indeed a smile to larger aperture, for it will appear much like a small comet with the nebulosity fanning away to the southwest. IC 2169 is the most difficult of all. Even with a large scope a “hint” is all!

Now, get out there and capture NGC 2261 (RA 6:39.2 Dec +08:44). You’ll find it about 2 degrees northeast of star 13 in Monoceros. Perhaps you know it better as “Hubble’s Variable Nebula”? Named for Edwin Hubble, this 10th magnitude object is very blue in appearance through larger apertures, and a true enigma. The fueling star, the variable R Monocerotis, does not display a normal stellar spectrum and may be a proto-planetary system. R is usually lost in the high surface brightness of the “comet-like” structure of the nebula, yet the nebula itself varies with no predictable timetable – perhaps due to dark masses shadowing the star. We do not even know how far away it is, because there is no detectable parallax!

There are many other wonderful objects in Monoceros just waiting for you to discover them… So get a good star atlas and go hunting the Unicorn!

Sources: Chandra Observatory, Wikipedia
Chart Courtesy of Your Sky.

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The small constellation of Microscopium resides just south of the ecliptic plane and was created by Nicolas Louis de Lacaille. It was adopted by the International Astronomical Union and accepted as one of the permanent 88 modern constellations. Microscopium covers approximately 210 square degrees of sky and contains 5 very dim stars in its asterism. It has 13 Bayer/Flamsteed designated stars within its confines and is bordered by the constellations of Capricornus, Sagittarius, Telescopium, Indus, Grus and Piscis Austrinus. It can be seen by observers located at latitudes between +45° and ?90° and is best seen at culmination during the month of September.

Because Microscopium is considered a “new” constellation, it has no mythology associated with it – but Nicolas Louis de Lacaille was a man of science and the constellation names he chose to add to his southern star catalog – Coelum Australe Stelliferum – favored this love of technological advances. During Lacaille’s time, the microscope wasn’t a particular new invention, having been created by Hans Lippershey (who also developed the first real telescope) over 100 years earlier, but it was making some serious optical advances when Anton van Leeuwenhoek’s work popularized it in Lacaille’s world. Although the dim stars bear no real resemblance to an actual microscope – who can fault him for his love of science and optics? After all… He was exploring the southern hemisphere with a half inch diameter spyglass and discovering all kinds of deep sky wonders!

Let’s begin our binocular tour of Microscopium with barely visible Alpha Microscopii – the “a” symbol on our map. At a distance of 380 light years from Earth, this G-class giant star shines with the candlepower of 163 Suns. It’s a helium fusing customer – busy working on developing its carbon-oxygen core and just minding its own business. Alpha ignited some 420 million years ago as a class B8 hydrogen-fusing dwarf and has been quiet ever since… But take a closer look in a telescope. Do you see a 10th magnitude companion star? Say hello to Alpha B. While many folks might argue that Alpha B isn’t a true binary star companion, research has shown that it has it has moved seven arc seconds closer to the primary since 1834. A pretty good indication or orbital motion, don’t you think?

Now turn your binoculars toward Theta 1 Microscopii – the curved “U1″ on our map. Here we have a variable star – but not by much. Theta1 Microscopii is an Alpha CV type star with a very small magnitude range of 4.77 to 4.87 every 2 days, 2 hours and 55 minutes. Not revealed on our map (because the symbols would be too close) is Theta 2 just to the southeast (21h 24.4m, -41 00′). Theta 2 is a very nice binary star, but it will require the use of a telescope at high magnification to split this 6.4 and 7th magnitude pair. Theta 1 and 2 will be a great optical double star for binoculars!

Get out the big telescope and let’s take a look at NGC 6925 (RA 20h 34.3m, Dec. -31 59′). At slightly fainter than magnitude 11, this inclined spiral galaxy is going to require dark skies to get a view, but it’s worth it. NGC 6925 is home to a mega-maser – water vapor being collected in the black hole of an active galactic nuclei! Look for a very stellar nucleus and just a wisp of extension.

More? Then try your luck with NGC 7057 (RA 21h 24m 58.5s Dec -42° 27′ 38.0”). This little elliptical galaxy runs around magnitude 12 and it isn’t going to be easy, either. What challenge is? Since it is a very isolated elliptical, it was used in studies to compare star formation rates between interacting and merging galaxies as opposed to those with no close companions. Believe it or not, according to Bergvall (et al) “from the global star formation aspect, generally (they) do not differ dramatically from scaled up versions of normal, isolated galaxies.”

How about IC 5105 (21h 24m 22.0s Dec -40° 32′ 14.0″)? Let us know if you see anything there! Supposedly there is an elliptical galaxy in this position and it has been studied for its stellar population and infrared emissions. Maybe we need infrared just to see it! Kinda’ like Microscopium, huh?

Sources:
http://www.ianridpath.com/startales/microscopium.htm
http://www.astro.wisc.edu/~dolan/constellations/constellations/Microscopium.html

Chart courtesy of Your Sky.

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The southern circumpolar constellation of Mensa was created by Nicolas Louis de Lacaille and was originally named Mons Mensae. It was later changed and adopted by the International Astronomical Union and accepted as one of the permanent 88 modern constellations. Mensa encompasses only 153 square degrees of sky – ranking 75th in size. It possesses no bright stars and only 4 stars form its cup-shaped asterism. There are, however, 16 Bayer/Flamsteed designated stars within its confines. Mensa is bordered by the constellations of Chamaeleon, Dorado, Hydrus, Octans and Volans. It is visible to observers positioned at latitudes between +18° and ?90° and is best seen at culmination during the month of January.

There is an annual meteor shower connected with this constellation is called the Delta Mensids – so named because the meteors appear to radiate from a point in the sky close to the star Delta Mensae. The meteor shower begins on or about March 14 and lasts until about March 21. Studies have shown there may be two seperate meteoriod streams responsible for this shower – one which causes a maximum on or about March 18 and another on or about March 19 with the debris suspected to have originated from Comet Pons, which was visible in 1804. Just as Mensa isn’t much of a constellation, the Delta Mensids aren’t much a meteor shower, either… The maximum fall rate only averages about 1 to 2 per hour at most.

Since Mensa is considered a relatively “new” constellation, there is no mythology associated with it, but there are several legends about how it came to be so named. It is believed that Nicolas Louis de Lacaille called in “Mons Mensae” in honor of Table Mountain, which overlooked his home observatory in Cape Town, South Africa. Since the top of the flat mountain was often covered by clouds, and the stellar formation is topped by the Large Magellanic Cloud, the name seems to fit perfectly! There is also a tall tale of a man who loved to smoke his pipe – but his wife forbid him to in the house. As a result, he would climb to the table mountain to enjoy the view while he smoked and one fine day he met the devil. Of course, he bragged how much he could smoke, so they engaged in a contest. The result left the mountain in a fog and the Magellanic Cloud in the stars! Other legendary tales suggest that our neighboring galaxy is either a god or a monster left on the high hill to guard the cape from unwary travelers… But no matter how Mensa came about its name, it is still a very faint constellation and will require patience and practice to see.

When you are ready, let’s start with a binocular tour of Mensa and its brightest star, Alpha – the “a” symbol on our map. Just barely visible to the unaided eye at magnitude 5.09 Alpha Mensae is a main sequence dwarf star located about 33 light years away from Earth. Shining away at about 80% the luminosity of our own Sun, Alpha is very similar. It is also a slow stellar rotator, taking about 32 days to complete a full rotation on its axis. At around 10 million years old, it comes within 7% of being about the same size as Sol, too… But we better enjoy it while we can. Even as we speak, Alpha Mensae is heading away from us at a speed of 35 kilometers per second!

Now aim your binoculars towards Beta Mensae – the “B” symbol on our map. Beta has the distinction of being a foreground star on the southern edge of the Large Magellanic Cloud! It’s a G-type giant star – again similar to our own Sun. What’s that? Try a main sequence star that’s happy in the “Yellow Evolutionary Void”. Unlike Alpha, it’s a lot further away… About 640 light years from our solar system.

Next stop? Pi Mensae – the “TT” symbol on our map. Pi is a yellow subgiant star with a high proper motion. Located approximately 60 light years away, Pi simply dwarfs our Sun in terms of mass, size, luminosity, temperature, and metallicity, yet it’s 730 million years younger! What makes it special? Pi ranks 100th on the list of top 100 target stars for the planned Terrestrial Planet Finder mission. On October 15, 2001, that search became successful when one of the most massive superjovian planets (HD 39091 b) ever found was discovered orbiting Pi Mensae. While it currently has a very eccentric orbit and takes approximately 2064 days (5.65 years) to revolve around its parent star, it does pass through a habitable zone – which means it probably would have disrupted the orbits of Earth-like planets long ago, either sending them into the parent star, or off into interstellar space.

While touring Mensa in binoculars, be sure to take in the full depth and breadth of the Large Magellanic Cloud which also crosses into Dorado. For a telescope challenge, try locating an open cluster in another galaxy! NGC 1711 (RA 04:50:36.0 Dec -69:59:06.0) is a very rich, 10th magnitude galactic star cluster which borders on the edge of being globular. It is actually a very young object whose data serves as a base for the study of mass functions and for the comparison with theoretical cosmological models.

For even more telescope challenges, try globular cluster NGC 2019 (RA 05:31:56:0). Also at home in the LMG, this small, bright-cored globular is a worthy target for mid-sized telescopes. Other globular clusters include NGC 2134, NGC 2065, NGC 2107, NGC 2058, NGC 1943, NGC 1987 and NGC 2121 in descending order of magnitude. These were all discovered by Sir William Herschel and are all located in the Mensa portion of the LMG.

Mensa is also home to quasar PKS 0637-752 (RA 06:35:46 Dec -75:16:12) – the first study of the Chandra X-Ray Observatory. When gathering first light on August 15, 1999, Chandra presented the world with a pair of images which revealed the quasar PKS0637-752 – a bright distant galaxy. Quasars like this are fairly “normal” galaxies which contain an active and massive black hole at its center. The brightness of the quasar is a result of material falling into the black hole. As well as the bright core of emission around the black hole, these images revealed a jet of material ejected from the black hole undergoing a remarkably sharp turn. With overlaying radio contours and optical images provided by Chandra, the newly revealed x-ray jet displayed the power far great than any radio jet ever recorded. It produces as much energy as 10 trillion Suns, all from a volume smaller than our own solar system!

Sources: Wikipedia, Chandra Observatory
Chart courtesy of Your Sky.

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Located north of the ecliptic plane, the constellation of Lyra is one of the original 48 constellations listed by Ptolemy, and remained as part of the 88 modern constellations recognized by the International Astronomical Union. Spanning only 286 square degrees of sky, Lyra ranks 52nd in size amongst the others, but contains the second brightest star in the northern hemisphere. Five main stars comprise its asterism and 25 Bayer Flamsteed designated stars are confined within its realm. Lyra is bordered by the constellations of Draco, Hercules, Vulpecula and Cygnus. It is visible to all viewers located at latitudes between +90° and ?40° and is best seen at culmination during the month of August.

There are two meteor showers associated with the constellation of Lyra. On or about April 22 of each year is the peak date of the annual Lyrid Meteor Shower. Its radiant – or where the meteors seem to originate – is around the bright star Vega. You can expect to see about 15 meteors per hour on the average when the constellation is at its highest on a dark night. They are bright, long-lasting meteors which leave long trails… the offspring of Comet Thatcher! The stream itself generally lasts through the beginning of May. By June 16, we return once again to hit another portion of the same stream, but with less force. The gravity of Jupiter and time has robbed this particular branch of the larger particles, so these meteors are much fainter. The fall rate also averages about 15 per hour maximum on a dark night – but the meteors are far fainter and tend to be more blue in color.

In mythology, Lyra is the “lyre”… a sort of hand-held harp. According to ancient Greeks, the messenger god Hermes created the lyre from the washed up body of a large tortoise shell which he covered with animal hide and antelope horns. He later gave it to Apollo as a present – who then presented it to his son Orpheus. There’s a wonderful quote by poet J.R. Lowell: “So there it lay, through wet and dry… As empty as the last new sonnet, Till by and by came Mercury, And, having mused upon it, ‘Why, here,’ cried he, ‘the thing of things In shape, material, and dimension! Give it but strings, and, lo, it sings, A wonderful invention!’ When Orpheus’ wife died, he was so grief stricken, he threw his harp into the Milky Way, wishing never to see it again. As legend has it, Apollo sent an eagle to retrieve it and set it among the stars. That is why you will also see it often depicted with wings as well. And so, the Lyre became part of the sky and it doesn’t take a whole lot of imagination to see its shape in the stars!

Now, let’s start our binocular tour of Lyra with its brightest star – Alpha – the “a” symbol on our map. Best known as Vega, it measures up as the second brightest star in the northern celestial hemisphere and the fifth brightest star in the night sky. Located 25.3 light years from Earth, this massively luminous A-type star is a suspected Delta-Scuti type variable star and its the first to have its spectrum photographed. Historically, Vega served as the northern pole star at about 12,000 BCE and will do so again at around 14,000 CE. Compared to our Sun, Vega is a youngster – with an unusually low abundance of the elements with a higher atomic number than that of helium. It’s also a rapid rotator – spinning completely on its axis in about 12 hours. So fast that the radius of the equator is 23% larger than the polar radius! Another thing Vega does have is an excess of infra-red radiation. What’s the cause? Possibly a circumstellar disc. Detections of irregularities in the disc means there’s a distinct chance of a planet the size of Jupiter orbiting there! I wonder how fast it orbits?

Keep your binoculars in hand and take a look at Beta Lyrae – the “B” symbol on our map. Now here’s a trick star system if there ever was one! Located 882 light-years from our solar system and named Sheliak, the “Tortoise” is very definitely a binary star – but not just any binary star. Sheliak is an eclipsing binary star. And not just any eclipsing binary star, but an eclipsing contact binary star system made up of a blue-white dwarf (B7V) star and a white main sequence (A8V) star. The two stars are close enough that material from the photosphere of each is pulled towards the other, drawing the stars into an ellipsoid shape. Beta Lyrae is the prototype for this class of eclipsing binaries, whose components are so close together that they deform by their mutual gravitation! In a period of period of 12.9075 days you’ll see this star swing drop from magnitude 3.4 to magnitude 4.6 – and it’s very noticeable. While you’ll never split the AB pair, you can very easily pick out the 7th magnitude C component with just your binoculars!

Don’t loose the binoculars yet. Head up to Delta 1 and Delta 2 – the figure “82” on our map. While the Delta pair is strictly an optical double star – this blue white and red pair of giant stars is very pleasing in binoculars. Slightly brighter, blue/white Delta 1 is located about 900 light years away and reddish Delta 2 is only about 720. Most of the time they are only separated by just a few tenths of a magnitude in brightness – but watch Delta 2 – because it is also a variable star and can become twice as dim! Did you happen to notice the pair is in a very stellar field? Good reason. Delta 1 and 2 are part of an open star cluster known as Stephenson 1.

Ready to have a look at Epsilon 2, the backwards “3” on our map? This is the famous “Double Double”. In binoculars you will see what appears to be a nice, white double star – but put a telescope at high magnification on it and watch what happens. Both stars will resolve into binary stars! The Epsilon Lyrae pair is one of the most observed multiple star systems in the heavens and the 162 light year distant mates make for a great time in just about any telescope – even in the most light polluted skies. Not only is each pair of stars physically connected to each other – but both pairs of stars are gravitationally bound – requiring over 12 centuries to complete their orbits. Are they close? You bet. If you have to wait for a moment of stability for them to cut themselves apart, then consider they’re only separated by about 0.16 of a light year!

And now for “Lucky 13″…

You can use binoculars, because star 13 is the infamous R Lyra – a proto-type variable star. Even though R is 350 light years away, its the brightest true (intrinsic) variable in the entire constellation. Sure, Beta looks brighter – but its changes come about because of eclipses – not because of internal processes. Inside of star 13 some mighty big changes are happening. Having progressed in its stellar evolution, this class M5 red giant star is also a semi-regular variable known as an SRb star – or a low-level, long period pulsating variable like Mira. Its changes are very noticeable, too… flipping between magnitude 3.9 and 5.0 over a 46 day period. Yes, it’s dying. And not a pretty death, either. Its mass is uncertain… It expands and contracts… its stellar temperature ranges from 3175 Kelvin to 3750 Kelvin… it has a dead carbon-oxygen core surrounded by fusing shells of helium… Apparently being star 13 isn’t so lucky!

Ready to get Messier? The go directly between Gamma and Beta Lyrae to grab the “Ring”… The only and only planetary nebula – M57. Discovered by French astronomer Antoine Darquier in 1779, the Ring Nebula was cataloged later that year by Charles Messier as M57 (RA 18 53 35 Dec +33 01 45). In binoculars the Ring will appear as slightly larger than a star, yet it cannot be focused to a sharp point. To a modest telescope at even low power, Messier 57 turns into a glowing donut against a wonderful stellar backdrop. The accepted distance to this unusual structure is about 1,400 light-years, and how you see the Ring on any given night is highly dependent on conditions. As aperture and power increase, so do details, and it is not impossible to see braiding in the nebula’s structure with scopes as small as 8″ on a fine night, or to pick up the star caught on the edge in even smaller apertures. Like all planetary nebulae, seeing the central star is considered the ultimate achievement in viewing. The central itself is a peculiar bluish dwarf which gives off a continuous spectrum, and might very well be a variable. At times, this shy, near 15th magnitude star can be seen with ease with a 12.5″ telescope, yet be elusive to even 31” in aperture weeks later. No matter what details you may see, reach for the “Ring” tonight. You’ll be glad you did.

More? Then hang on and let’s go globular cluster hunting as we capture Messier 56! Located roughly midway between Beta Cygni and Gamma Lyrae (RA 19 15 35.50 Dec +30 11 04.2), this class X globular was discovered by Charles Messier in 1779 on the same night he discovered a comet, and was later resolved by Herschel. At magnitude 8 and small in size, it’s a tough call for a beginner with binoculars, but is a very fine telescopic object. With a general distance of 33,000 light-years, this globular resolves well with larger scopes, but doesn’t show as much more than a faint, round area with small aperture. However, the beauty of the chains of stars in the field makes it quite worth the visit!

While you’re there, look carefully: M56 is one of the very few objects for which the photometry of its variable stars was studied strictly with amateur telescopes. While one bright variable had been known previously, up to a dozen more have recently been discovered. Of those, six had their variability periods determined using CCD photography and telescopes just like yours!

For a big telescope challenge, try your luck with NGC 6702 (RA 18:47.0 Dec +45:42). This magnitude 12, this small, faint elliptical galaxy was home to a supernovae event in 2002 and has a high evolved and highly studied globular cluster system. For a slightly brighter galaxy, look up very nearby NGC 6703 (RA 18:47.3 Dec +45:33) to the southeast. Also an elliptical galaxy, but a full magnitude brighter and slightly larger, you’ll pick out a more round signature in this one. Studies have found a dust lane in the center of NGC 6702 indicating a recent gaseous galaxy merger event meaning this pair are truly and interacting set.

Sources: SEDS, Wikipedia
Chart courtesy of Your Sky.

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Located north of the ecliptic plane, the dim constellation of Lynx was first introduced in the 17th century by Johannes Hevelius in 1687 and later recognized as one of the 88 modern constellations by the International Astronomical Union. According to legend, Lynx is so named because it is a relatively faint constellation, and one would supposedly need the eyes of a lynx to see it. Covering 545 square degrees of sky, it ranks as the 28th largest constellation. Although only 4 main stars form its asterism, Lynx contains 42 stars with Bayer Flamsteed designations. It is bordered by the constellations of Ursa Major, Camelopardalis, Auriga, Gemini, Cancer, Leo and Leo Minor. Lynx is visible to all observers located at latitudes between +90° and ?55° and is best seen at culmination during the month of March.

Since Lynx wasn’t recognized as a constellation until the 17th century, it has no mythology associated with it and it would seem that Hevelius was merely trying to fill in the spaces between the constellations by making up a mythical figure – or was he? Actually, by doing a little research into the life and times of Johannes Hevelius, you might find that he was a very interesting figure and very devoted to nature studies – in particular North America. At the time the lynx was a native of Europe, but hunted almost to the point of extinction. Not so in a new land. To Native Americans, the lynx was legendary – an elusive, ghost-like animal that sees without being seen. It was known as “the keeper of secrets of the forest” and to see it was quite magical – knowing that its secrecy was its strength. Oddly enough, the lynx was chosen as the emblem of the Accademia dei Lincei (“Academy of the Lynxes”), one of the world’s oldest scientific societies. Its piercing vision was invoked symbolically as characteristic of those dedicated to science. So perhaps good old Hevelius wasn’t quite as prone to “filling in the blanks” as we thought, eh?

Now, grab your binoculars and let’s take a look at the only star that Bayer (shame on him) got around to giving a Greek letter to – Alpha Lyncis – the “a” symbol on our map. At 220 light years from Earth, class K (K7) giant star Alpha has no proper name, yet it still burns merrily away at a rough stellar temperature of 3860 degrees Kelvin. It is about a billion and a half years old and perhaps not very special except for it is about 700 times brighter than our own Sun. However, take a look at its twin, star 31. Now, this one did get a name – Alsciaukat – the “Thorn”. It is almost identical to Alpha in every respect, only slightly further away at 390 light years. Their luminousities, their temperatures, their sizes, their ages… Almost twins! Only this time Alsciaukat is also a slight variable star, changing by about .05 magnitude. Why is it a bit different? Chances are it is brightening for the second time – gearing up to become a long term variable like Mira.

For the telescope, have a look at 38 Lyncis. Hevelius wasn’t without a sense of humor, because he named this one Maculosa and Maculata, which synonymously mean “The Spotted One”. Can you guess why? That’s right. It’s because 38 Lyncis is a binary star. Located about 120 light years from our solar system, this star has several components. The 3.9 primary star is also a spectroscopic binary, but look for the near 7th magnitude C star to split easily away and a very widely spaced 11th magnitude D companion, too. While the primary star usually appears to be white in color, look for a slight green tinge, as well as some blue coloration to the C star, too. The double star is on many observing lists!

Now, check out wide visual triple star, 12 Lyncis. Also on a host of observing lists, this one is very easy and very rewarding to small telescopes. Look for a 5.4 primary star accompanied by the 6.0 B star and the further spaced 7.3 magnitude C star. Located about 230 light years away, you can thank Otto Struve for discovering this one in 1828!

For variable star fans, be sure to keep an eye on R Lyncis (RA 07:01:18 Dec +55:19:50). It’s a great Mira-type variable that also does a disappearing act! For a long period of time, R appears as a rather ordinary red 7th magnitude star…. then it drops off the map when it falls down to magnitude 14.3. Weird? Darn right. R Lyncis belongs to a small group of long-period variables with a “S” spectrum – a ‘cool red giant’ that shows the presence of zirconium oxide.

Now we’ll put our “cat’s eyes”, grab our telescopes and go in search of one of the most distant objects in our Galaxy – NGC 2419 (RA 07:38:08.51 Dec +38:52:54). As a telescopic object only, this magnitude 11.5 study requires clear dark skies and at least 150mm of aperture. Since Lynx is a difficult constellation, you will find this easier by going 7 degrees north of Castor. You will know if you have the correct field if two stars appear to the western edge of a hazy patch. There is a very good reason “why” this elusive globular cluster is so special! Most commonly known as “the Intergalactic Wanderer”, the NGC 2419 is so distant that it was at one time believed to actually be outside our own galaxy. Almost all globular clusters are found within our galactic “halo” – a region which exists about 65,000 light years around the galactic center. Our faint friend here is at least 210,000 light years from where it should be! When I tell you it’s out there… I’m not kidding. The NGC 2419 is as distant as our galactic “neighbors”, the Magellanic Clouds! But don’t worry, our Galaxy has sufficient gravitation to keep “the Intergalactic Wanderer” around long enough for you to capture it for yourself!

Ready for more? Then keep the telescope out as we journey towards spiral galaxy NGC 2683 (RA 08:52.7 Dec +33:25). Located 16000 light years away from our own Milky Way Galaxy, this superb edge-on was discovered by William Herschel on February 5, 1788. Holding a bright and respectable magnitude 10 puts it well within realm of smaller telescopes and larger ones will be able to pick out varying degrees of spiral galaxy structure, including hints of a dark dust lane and a bright, bulging nucleus. It’s a Herschel 400 object, so be sure to mark your notes!

Need a challenge? Then try your luck with NGC 2776 (RA 9:12.2 Dec +44:57). At near 12th magnitude, this small spiral galaxy isn’t going to be easy, but a large telescope can handle it. Viewed perfectly face-on, look for the signature round structure with a bright core region and some resolution of arms during good seeing conditions. More? How about 13th magnitude barred spiral galaxy IC 2233 (RA 08:13:58 Dec +45 44:32). Sometimes known as the “Needle” because of its edge-on presentation!

Sources: Chandra Observatory, Wikipedia, SEDS
Chart courtesy of Your Sky.